class Game
  attr_accessor :price, :title
  def initialize(title = "DNF", price = 200)
    @title = title
    @price = price
  end
  def show()
    puts "标题：#{@title}"
    puts "价格：#{@price}"
  end
  def show2()

  end
  def show3()

  end
end

puts Game.instance_methods(false)

mario = Game.new("LOL", 500)
if mario.respond_to?("show")
  mario.show()
else
  puts "没有方法"
end

mygame = Game.new()
mygame.show()

puts "title is" + mygame.respond_to?("title").to_s
puts "price is" + mygame.respond_to?("price").to_s

mygame.title = "毒奶粉"
mygame.price = "20000"
mygame.show()

puts "a"*4

puts "a" << "b"

puts "a\nb"

puts 'a\nb'

puts "#{20+30+40}"

puts '#{20+30+40}'

mvp_rank = {
    "currency" => "USD",
    "amount" => 800
}

puts mvp_rank
puts mvp_rank["currency"]

payyer = {
    "currency": "DNF",
    "amount": 200
}

puts payyer[:amount]

p "hello"